Use immutable sequence type for batch/batch_as_completed types (#22433)

Thank you for contributing to LangChain!

- [ ] **PR title**: "package: description"
- Where "package" is whichever of langchain, community, core,
experimental, etc. is being modified. Use "docs: ..." for purely docs
changes, "templates: ..." for template changes, "infra: ..." for CI
changes.
  - Example: "community: add foobar LLM"


- [ ] **PR message**: ***Delete this entire checklist*** and replace
with
    - **Description:** a description of the change
    - **Issue:** the issue # it fixes, if applicable
    - **Dependencies:** any dependencies required for this change
- **Twitter handle:** if your PR gets announced, and you'd like a
mention, we'll gladly shout you out!


- [ ] **Add tests and docs**: If you're adding a new integration, please
include
1. a test for the integration, preferably unit tests that do not rely on
network access,
2. an example notebook showing its use. It lives in
`docs/docs/integrations` directory.


- [ ] **Lint and test**: Run `make format`, `make lint` and `make test`
from the root of the package(s) you've modified. See contribution
guidelines for more: https://python.langchain.com/docs/contributing/

Additional guidelines:
- Make sure optional dependencies are imported within a function.
- Please do not add dependencies to pyproject.toml files (even optional
ones) unless they are required for unit tests.
- Most PRs should not touch more than one package.
- Changes should be backwards compatible.
- If you are adding something to community, do not re-import it in
langchain.

If no one reviews your PR within a few days, please @-mention one of
baskaryan, efriis, eyurtsev, ccurme, vbarda, hwchase17.

libs/core/langchain_core/runnables/base.py

@@ -642,8 +642,8 @@ class Runnable(Generic[Input, Output], ABC):
     @overload
     def batch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: Literal[False] = False,
         **kwargs: Any,
@@ -653,8 +653,8 @@ class Runnable(Generic[Input, Output], ABC):
     @overload
     def batch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: Literal[True],
         **kwargs: Any,
@@ -663,8 +663,8 @@ class Runnable(Generic[Input, Output], ABC):
 
     def batch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: bool = False,
         **kwargs: Optional[Any],
@@ -746,8 +746,8 @@ class Runnable(Generic[Input, Output], ABC):
     @overload
     def abatch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: Literal[False] = False,
         **kwargs: Optional[Any],
@@ -757,8 +757,8 @@ class Runnable(Generic[Input, Output], ABC):
     @overload
     def abatch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: Literal[True],
         **kwargs: Optional[Any],
@@ -767,8 +767,8 @@ class Runnable(Generic[Input, Output], ABC):
 
     async def abatch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: bool = False,
         **kwargs: Optional[Any],
@@ -4506,8 +4506,8 @@ class RunnableBindingBase(RunnableSerializable[Input, Output]):
     @overload
     def batch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: Literal[False] = False,
         **kwargs: Any,
@@ -4517,8 +4517,8 @@ class RunnableBindingBase(RunnableSerializable[Input, Output]):
     @overload
     def batch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: Literal[True],
         **kwargs: Any,
@@ -4527,13 +4527,13 @@ class RunnableBindingBase(RunnableSerializable[Input, Output]):
 
     def batch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: bool = False,
         **kwargs: Optional[Any],
     ) -> Iterator[Tuple[int, Union[Output, Exception]]]:
-        if isinstance(config, list):
+        if isinstance(config, Sequence):
             configs = cast(
                 List[RunnableConfig],
                 [self._merge_configs(conf) for conf in config],
@@ -4559,8 +4559,8 @@ class RunnableBindingBase(RunnableSerializable[Input, Output]):
     @overload
     def abatch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: Literal[False] = False,
         **kwargs: Optional[Any],
@@ -4570,8 +4570,8 @@ class RunnableBindingBase(RunnableSerializable[Input, Output]):
     @overload
     def abatch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: Literal[True],
         **kwargs: Optional[Any],
@@ -4580,13 +4580,13 @@ class RunnableBindingBase(RunnableSerializable[Input, Output]):
 
     async def abatch_as_completed(
         self,
-        inputs: List[Input],
+        inputs: Sequence[Input],
-        config: Optional[Union[RunnableConfig, List[RunnableConfig]]] = None,
+        config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]] = None,
         *,
         return_exceptions: bool = False,
         **kwargs: Optional[Any],
     ) -> AsyncIterator[Tuple[int, Union[Output, Exception]]]:
-        if isinstance(config, list):
+        if isinstance(config, Sequence):
             configs = cast(
                 List[RunnableConfig],
                 [self._merge_configs(conf) for conf in config],

libs/core/langchain_core/runnables/config.py

@@ -18,6 +18,7 @@ from typing import (
     Iterator,
     List,
     Optional,
+    Sequence,
     TypeVar,
     Union,
     cast,
@@ -159,7 +160,7 @@ def ensure_config(config: Optional[RunnableConfig] = None) -> RunnableConfig:
 
 
 def get_config_list(
-    config: Optional[Union[RunnableConfig, List[RunnableConfig]]], length: int
+    config: Optional[Union[RunnableConfig, Sequence[RunnableConfig]]], length: int
 ) -> List[RunnableConfig]:
     """Get a list of configs from a single config or a list of configs.
 
@@ -179,13 +180,13 @@ def get_config_list(
     """
     if length < 0:
         raise ValueError(f"length must be >= 0, but got {length}")
-    if isinstance(config, list) and len(config) != length:
+    if isinstance(config, Sequence) and len(config) != length:
         raise ValueError(
             f"config must be a list of the same length as inputs, "
             f"but got {len(config)} configs for {length} inputs"
         )
 
-    if isinstance(config, list):
+    if isinstance(config, Sequence):
         return list(map(ensure_config, config))
     if length > 1 and isinstance(config, dict) and config.get("run_id") is not None:
         warnings.warn(